Why does the speed of a planet decrease as it moves away from the sun?(1 point) Responses The sun’s gravitational pull on the sun decreases. The sun’s gravitational pull on the sun decreases. The planet’s inertia begins to point inward toward the sun. The planet’s inertia begins to point inward toward the sun. The planet’s inertia begins to point backward along its orbit. The planet’s inertia begins to point backward along its orbit. The direction of the sun’s pull relative to the planet’s motion changes.

Question

Why does the speed of a planet decrease as it moves away from the sun?(1 point) Responses The sun’s gravitational pull on the sun decreases. The sun’s gravitational pull on the sun decreases. The planet’s inertia begins to point inward toward the sun. The planet’s inertia begins to point inward toward the sun. The planet’s inertia begins to point backward along its orbit. The planet’s inertia begins to point backward along its orbit. The direction of the sun’s pull relative to the planet’s motion changes.

Answer 1

The correct response is: The direction of the sun’s pull relative to the planet’s motion changes.

Answer 2

The correct answer is: The direction of the sun’s pull relative to the planet’s motion changes.

As a planet moves away from the sun, the direction of the sun's gravitational pull relative to the planet's motion changes. The gravitational force between the planet and the sun acts as a centripetal force, keeping the planet in its orbit. However, as the planet moves away, the force of gravity starts to act more perpendicular to the direction of the planet's motion, causing a decrease in the planet's speed. This change in the direction of the force counteracts the planet's forward motion, resulting in a decrease in its speed.

Answer 3

The correct response to the question is: "The planet’s inertia begins to point backward along its orbit." When a planet moves away from the sun, its inertia, or tendency to continue moving in a straight line, starts to point backwards, opposite to its direction of motion along its orbit. As a result, the speed of the planet decreases.

To understand this concept, it's helpful to consider Newton's first law of motion, which states that an object in motion will stay in motion unless acted upon by an external force. In the case of a planet orbiting the sun, the planet is constantly being pulled towards the sun by gravity. This gravitational force acts as the external force that continuously changes the direction of the planet's motion, causing it to move in a curved path, or an orbit, around the sun.

As the planet moves away from the sun, the gravitational pull of the sun becomes weaker. However, the planet still possesses its inertia, which tends to make it continue moving in a straight line. Due to the changing strength of the sun's gravity, the direction of the net force acting on the planet changes. This change in force causes the planet's inertia to start pointing backward along its orbit. As a result, the planet's speed decreases as it moves farther away from the sun.

Understanding the concept of inertia and its relationship to the forces acting on an object is fundamental in explaining why the speed of a planet decreases as it moves away from the sun.